Banana streak viruses
Banana streak viruses (BSV) form a complex of viral species that cause streak disease. The species belong to the Badnavirus genus and the Caulimoviridae family. Unlike most plant viruses, the genome of these viruses is composed of DNA rather than RNA.
All the isolates used to be considered as belonging to the same species, but some of them have since been shown to be separate species. The viruses exist in episomal form but are also integrated in the DNA of Musa balbisiana and as a result have been found in banana cultivars that have the B genome. Even though not all integrated sequences can trigger an infection, their presence has been a constraint on the movement of genebank accessions that have the B genome.
The viruses have non-enveloped, bacilliform particles measuring ca 130-150 x 30 nm and containing a circular dsDNA genome of 7.4 kb.